The present invention relates to an apparatus and a method for helping to protect a vehicle occupant during a vehicle collision.
A known apparatus for helping to protect a vehicle occupant, as disclosed in the Japanese patent application to Imai, No. 4-110251(A), includes an inflatable vehicle occupant protection device. The apparatus also includes an inflator for providing inflation fluid to inflate the inflatable vehicle occupant protection device. A cover for the apparatus has a set of tear seams and a separate single tear seam that release upon inflation of the inflatable vehicle occupant protection device.
In operation, the set of tear seams release prior to the single tear seam, and the inflatable vehicle occupant protection device expands to the left and the right of the vehicle occupant. The single tear seam releases subsequent to the set of tear seams, and the inflatable vehicle occupant protection device then fully inflates.
A cover that would help the inflatable vehicle occupant protection device to reposition a vehicle occupant, under certain conditions during deployment, could reduce the forces to which the occupant is exposed.
In accordance with the present invention, an apparatus for helping to protect a vehicle occupant includes an inflatable vehicle occupant protection device, an inflator, and a cover for the inflatable vehicle occupant protection device. The inflator provides inflation fluid to inflate the inflatable vehicle occupant protection device. The cover has a front wall positioned between the vehicle occupant and the inflatable vehicle occupant protection device. The front wall includes a center section interposed between a first side section of the front wall and a second side section of the front wall.
The cover has at least one strong tear seam and at least one weak tear seam. The weak tear seam releases when subjected to a first force by the inflatable vehicle occupant protection device. The strong tear seam thereafter releases. The inflatable vehicle occupant protection device, while being inflated and releasing the weak tear seam, moves at least one of the side sections away from the center section. The inflatable vehicle occupant protection device deploys through a first area that is provided by moving the at least one side section. The inflatable vehicle occupant protection device, while deploying, urges a vehicle occupant away from the front wall. Thereafter, the strong tear seam releases, and the center section of the front wall moves away from the first area. The inflatable vehicle occupant protection device then deploys through a second area that is provided by moving the center section and becomes fully inflated.
The present invention also involves a method for helping to protect a vehicle occupant. The method comprises providing an inflatable vehicle occupant protection device and an inflator for providing inflation fluid to inflate the vehicle occupant protection device. The vehicle occupant protection device is covered with a cover having a front wall. The front wall is positioned between the vehicle occupant and the inflatable vehicle occupant protection device. The front wall includes a center section interposed between a first side section of said cover and a second side section of said cover. The cover has at least one strong tear seam and at least one weak tear seam.
The method includes releasing the at least one weak tear seam by subjecting the at least one weak tear seam to a first force by the inflatable vehicle occupant protection device, and thereafter releasing the at least one strong tear seam. In the method, the inflatable vehicle occupant protection device, while being inflated, releases the at least one weak tear seam and moves at least one of said side sections away from the center section. The inflatable vehicle occupant protection device deploys through a first area that is provided by moving the at least one side section. The inflatable vehicle occupant protection device urges a vehicle occupant away from the center section. Thereafter, the at least one strong tear seam releases, and the center section is moved away from the first area. The inflatable vehicle occupant protection device then deploys through a second area that is provided by moving the center section and becomes fully inflated.